In my experience, there seems to be some sort of "Aspie-look" that us people with Aspergers and Autism have.
I can't really describe it at all, it's just something I know when I see it.
Even just looking at a picture of someone with AS, there's something about the way they look that makes me all the more likely to believe they have it.
Of course, I am making a big generalization, here, but I think it's an interesting thing to think about.
An example is a friend at school has Autism (severe, he has learning difficulties). His older brother also has Aspergers, I could instantly tell the moment I met him. He was just chillin' out, looking normal. But yeah. Talking to him a little more has made me pick up on his aspie trait better.
Anyway, sorry for going on and on, but yeah. Does anyone else believe in the "aspie-look"? That only by physical appearance can we occasionally make a good guess if someone else has what we have?